package com.example.demo.config;

import com.example.demo.common.AppVariable;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * @program: demo
 * @author: JCM
 * @create: 2023-07-31 21:40
 * @description: 登录拦截器
 **/
public class LoginInterceptor implements HandlerInterceptor {

    /**
     * true --> 用户已登录， false --> 用户未登录
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        HttpSession session = request.getSession(false);
        if(session != null && session.getAttribute(AppVariable.USER_SESSION_KEY) != null) {
            // 用户已登录
            return  true;
        }
        response.sendRedirect("/login.html");
        return false;
    }
}
